Heat pack



FIG. 1 is a perspective view of a heat pack, showing my new design;

FIG. 2 is a side elevational view thereof, the opposite side elevational view being identical thereto;

FIG. 3 is a top plan view thereof, the bottom plan view being a mirror image thereof; and,

FIG. 4 is another side elevational view thereof, the opposite side elevational view being identical thereto. 

The ornamental design for a heat pack, as shown and described. 